xref: /onnv-gate/usr/src/common/openssl/crypto/rand/randfile.c (revision 2139:6243c3338933)
1 /* crypto/rand/randfile.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 /*
60  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
61  * Use is subject to license terms.
62  */
63 
64 #pragma ident	"%Z%%M%	%I%	%E% SMI"
65 
66 /* We need to define this to get macros like S_IFBLK and S_IFCHR */
67 #ifndef	_BOOT
68 #define _XOPEN_SOURCE 500
69 #endif	/* _BOOT */
70 
71 #include <errno.h>
72 #include <stdio.h>
73 #include <stdlib.h>
74 #include <string.h>
75 
76 #include "e_os.h"
77 #include <openssl/crypto.h>
78 #include <openssl/rand.h>
79 #include <openssl/buffer.h>
80 
81 #ifdef OPENSSL_SYS_VMS
82 #include <unixio.h>
83 #endif
84 #ifndef NO_SYS_TYPES_H
85 # include <sys/types.h>
86 #endif
87 #ifdef MAC_OS_pre_X
88 # include <stat.h>
89 #else
90 # include <sys/stat.h>
91 #endif
92 
93 #undef BUFSIZE
94 #define BUFSIZE	1024
95 #define RAND_DATA 1024
96 
97 /* #define RFILE ".rnd" - defined in ../../e_os.h */
98 
99 /* Note that these functions are intended for seed files only.
100  * Entropy devices and EGD sockets are handled in rand_unix.c */
101 
RAND_load_file(const char * file,long bytes)102 int RAND_load_file(const char *file, long bytes)
103 	{
104 	/* If bytes >= 0, read up to 'bytes' bytes.
105 	 * if bytes == -1, read complete file. */
106 
107 	MS_STATIC unsigned char buf[BUFSIZE];
108 	struct stat sb;
109 	int i,ret=0,n;
110 	FILE *in;
111 
112 	if (file == NULL) return(0);
113 
114 	i=stat(file,&sb);
115 	/* If the state fails, put some crap in anyway */
116 	RAND_add(&sb,sizeof(sb),0.0);
117 	if (i < 0) return(0);
118 	if (bytes == 0) return(ret);
119 
120 	in=fopen(file,"rb");
121 	if (in == NULL) goto err;
122 #if defined(S_ISBLK) && defined(S_ISCHR)
123 	if (S_ISBLK(sb.st_mode) || S_ISCHR(sb.st_mode)) {
124 	  /* this file is a device. we don't want read an infinite number
125 	   * of bytes from a random device, nor do we want to use buffered
126 	   * I/O because we will waste system entropy.
127 	   */
128 	  bytes = (bytes == -1) ? 2048 : bytes; /* ok, is 2048 enough? */
129 	  setvbuf(in, NULL, _IONBF, 0); /* don't do buffered reads */
130 	}
131 #endif
132 	for (;;)
133 		{
134 		if (bytes > 0)
135 			n = (bytes < BUFSIZE)?(int)bytes:BUFSIZE;
136 		else
137 			n = BUFSIZE;
138 		i=fread(buf,1,n,in);
139 		if (i <= 0) break;
140 		/* even if n != i, use the full array */
141 		RAND_add(buf,n,(double)i);
142 		ret+=i;
143 		if (bytes > 0)
144 			{
145 			bytes-=n;
146 			if (bytes <= 0) break;
147 			}
148 		}
149 	fclose(in);
150 	OPENSSL_cleanse(buf,BUFSIZE);
151 err:
152 	return(ret);
153 	}
154 
RAND_write_file(const char * file)155 int RAND_write_file(const char *file)
156 	{
157 	unsigned char buf[BUFSIZE];
158 	int i,ret=0,rand_err=0;
159 	FILE *out = NULL;
160 	int n;
161 	struct stat sb;
162 
163 	i=stat(file,&sb);
164 	if (i != -1) {
165 #if defined(S_ISBLK) && defined(S_ISCHR)
166 	  if (S_ISBLK(sb.st_mode) || S_ISCHR(sb.st_mode)) {
167 	    /* this file is a device. we don't write back to it.
168 	     * we "succeed" on the assumption this is some sort
169 	     * of random device. Otherwise attempting to write to
170 	     * and chmod the device causes problems.
171 	     */
172 	    return(1);
173 	  }
174 #endif
175 	}
176 
177 #if defined(O_CREAT) && !defined(OPENSSL_SYS_WIN32)
178 	{
179 	/* For some reason Win32 can't write to files created this way */
180 
181 	/* chmod(..., 0600) is too late to protect the file,
182 	 * permissions should be restrictive from the start */
183 	int fd = open(file, O_CREAT, 0600);
184 	if (fd != -1)
185 		out = fdopen(fd, "wb");
186 	}
187 #endif
188 	if (out == NULL)
189 		out = fopen(file,"wb");
190 	if (out == NULL) goto err;
191 
192 #ifndef NO_CHMOD
193 	chmod(file,0600);
194 #endif
195 	n=RAND_DATA;
196 	for (;;)
197 		{
198 		i=(n > BUFSIZE)?BUFSIZE:n;
199 		n-=BUFSIZE;
200 		if (RAND_bytes(buf,i) <= 0)
201 			rand_err=1;
202 		i=fwrite(buf,1,i,out);
203 		if (i <= 0)
204 			{
205 			ret=0;
206 			break;
207 			}
208 		ret+=i;
209 		if (n <= 0) break;
210                 }
211 #ifdef OPENSSL_SYS_VMS
212 	/* Try to delete older versions of the file, until there aren't
213 	   any */
214 	{
215 	char *tmpf;
216 
217 	tmpf = OPENSSL_malloc(strlen(file) + 4);  /* to add ";-1" and a nul */
218 	if (tmpf)
219 		{
220 		strcpy(tmpf, file);
221 		strcat(tmpf, ";-1");
222 		while(delete(tmpf) == 0)
223 			;
224 		rename(file,";1"); /* Make sure it's version 1, or we
225 				      will reach the limit (32767) at
226 				      some point... */
227 		}
228 	}
229 #endif /* OPENSSL_SYS_VMS */
230 
231 	fclose(out);
232 	OPENSSL_cleanse(buf,BUFSIZE);
233 err:
234 	return (rand_err ? -1 : ret);
235 	}
236 
RAND_file_name(char * buf,size_t size)237 const char *RAND_file_name(char *buf, size_t size)
238 	{
239 	char *s=NULL;
240 	int ok = 0;
241 #ifdef __OpenBSD__
242 	struct stat sb;
243 #endif
244 
245 	if (OPENSSL_issetugid() == 0)
246 		s=getenv("RANDFILE");
247 	if (s != NULL && *s && strlen(s) + 1 < size)
248 		{
249 		if (BUF_strlcpy(buf,s,size) >= size)
250 			return NULL;
251 		}
252 	else
253 		{
254 		if (OPENSSL_issetugid() == 0)
255 			s=getenv("HOME");
256 #ifdef DEFAULT_HOME
257 		if (s == NULL)
258 			{
259 			s = DEFAULT_HOME;
260 			}
261 #endif
262 		if (s && *s && strlen(s)+strlen(RFILE)+2 < size)
263 			{
264 			BUF_strlcpy(buf,s,size);
265 #ifndef OPENSSL_SYS_VMS
266 			BUF_strlcat(buf,"/",size);
267 #endif
268 			BUF_strlcat(buf,RFILE,size);
269 			ok = 1;
270 			}
271 		else
272 		  	buf[0] = '\0'; /* no file name */
273 		}
274 
275 #ifdef __OpenBSD__
276 	/* given that all random loads just fail if the file can't be
277 	 * seen on a stat, we stat the file we're returning, if it
278 	 * fails, use /dev/arandom instead. this allows the user to
279 	 * use their own source for good random data, but defaults
280 	 * to something hopefully decent if that isn't available.
281 	 */
282 
283 	if (!ok)
284 		if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {
285 			return(NULL);
286 		}
287 	if (stat(buf,&sb) == -1)
288 		if (BUF_strlcpy(buf,"/dev/arandom",size) >= size) {
289 			return(NULL);
290 		}
291 
292 #endif
293 	return(buf);
294 	}
295